Can't disable push email?

I went to my local Verizon store with the intent of buying a Treo 600, but the salesman told me that it has "push email" feature that cannot be turned off. He said that I had to either pay for data service, or the Treo would constantly burn up my voice minutes by polling the network.

Is this true? Does the Treo 600 really have a polling feature that cannot be disabled?